Cooper said in the liner notes of Fistful of Alice and In the Studio with Redbeard, which spotlighted the Killer and Love it to Death albums, that the song "Desperado" was written about his friend Jim Morrison, who died the year this album was released. According to an NPR radio interview with Alice Cooper, "Desperado" was written about Robert Vaughn's character from the movie The Magnificent Seven. "Halo of Flies" was, according to Cooper's liner notes in the compilation The Definitive Alice Cooper, an attempt by the band to prove that they could perform King Crimson-like progressive rock suites, and was supposedly about a SMERSH-like organisation. "Desperado", along with "Under My Wheels" and "Be My Lover" have appeared on different compilation albums by Cooper. The song "Dead Babies" stirred up some controversy following the album's release, despite the fact that its lyrics conveyed an "anti-child abuse" message. Musicians such as Jello Biafra and John Lydon have referred to the album as an influence.

Rolling Stone's Lester Bangs gave it a favorable review. He explained that "it brings all the elements of the band's approach to sound and texture to a totally integrated pinnacle that fulfills all the promise of their erratic first two albums" and that "each song on [the] album finds him in a different role in the endless movie he is projecting on them." He concluded by calling Alice Cooper "a strong band, a vital band, and they are going to be around for a long, long time."[2] Robert Christgau rated the album a B-, stating that "a taste for the base usages of hard rock rarely comes with a hit attached these days, much less "surreal," "theatrical," and let us not forget "transvestite" trappings". However, he said that "[the album] falters after "Under My Wheels" and "Be My Lover," neither of them an "I'm Eighteen" in the human outreach department."[3] AllMusic's Greg Prato rated "Killer" four-and-a-half out of five stars. He stated that "disturbing tracks [...] fit in perfectly" and that "other songs were even more exceptional". He concluded by pointing out that "it rewarded them as being among the most notorious and misunderstood entertainers, thoroughly despised by grownups."[1]